Find the first four terms, in ascending powers of xxx, of the binomial expansion of 1+8x \sqrt{1 + 8x}\,1+8x giving each term in its simplest form.
Explain how you could use x=332\displaystyle x = \frac{3}{32}x=323 in the expansion to find an approximation for 7\sqrt{7}7. There is no need to carry out the calculation.
408 exam-style questions on Edexcel A Level Maths Binomial Expansion, covering 4.1 Expanding (1 + x)^n, 4.2 Expanding (a + bx)^n, and 4.3 Using Partial Fractions. Each one has a worked solution and a mark scheme showing where the marks go.